Lost-wax casting

Lost-wax casting (also called 'investment casting', 'precision casting', or cire perdue which has been adopted into English from the French) is the process by which a duplicate metal sculpture (often silver, gold, brass or bronze) is cast from an original sculpture. Intricate works can be achieved by this method. This bronze piece entitled Lazy Lady, by the sculptor Rowan Gillespie was cast using the lost-wax process.Hugo Rheinhold's Affe mit Schädel is cast out of bronze using the lost-wax process.A wax model is sprued with vents for casting metal and for the release of air, and covered in heat-resistant material.A cast in bronze, still with spruingA bronze cast, with part of the spruing cut awayA nearly finished bronze casting. Only the core supports have yet to be removed and closedIllustration of stepwise bronze casting by the lost-wax methodThe Blätterbrunnen of 1976 by Emil Cimiotti, as seen 2014 in the city center of Hanover, Germany. A lost-wax method was used for the bronze leaves. Lost-wax casting (also called 'investment casting', 'precision casting', or cire perdue which has been adopted into English from the French) is the process by which a duplicate metal sculpture (often silver, gold, brass or bronze) is cast from an original sculpture. Intricate works can be achieved by this method. The oldest known example of this technique is a 6,000-year old amulet from Indus valley civilization. Other examples from a similar period are the objects discovered in the Cave of the Treasure (Nahal Mishmar) hoard in southern Israel, and which belong to the Chalcolithic period (4500–3500 BC). Conservative estimates of age from carbon-14 dating date the items to c. 3700 BC, making them more than 5,700 years old.. Lost-wax casting was widespread in Europe until the 18th century, when a piece-moulding process came to predominate. The steps used in casting small bronze sculptures are fairly standardized, though the process today varies from foundry to foundry. (In modern industrial use, the process is called investment casting.) Variations of the process include: 'lost mould', which recognizes that materials other than wax can be used (such as: tallow, resin, tar, and textile); and 'waste wax process' (or 'waste mould casting'), because the mould is destroyed to remove the cast item.